Heterojunction switching and memory device

ABSTRACT

A BISTABLE SWITCHING AND NON-VOLATILE MEMORY DEVICE WHICH MAY BE READ EITHER DESTRUCTIVELY OR NON-DESTRUCTIVELY IS PROVIDED, AS SHOWN IN FIG. 5, USING A HETEROJUNCTION CONSISTING OF A HEAVILY DOPED, SINGLE CRYSTAL, SEMICONDUCTING MATERIAL IN ELECTRICAL AND MECHANICAL CONTACT WITH A DIFFERENT, HIGH RESISTIVITY, SEMICONDUCTING MATERIAL. MTHE HETEROJUNCTION EXHIBITS STABLE HIGH AND LOW IMPEDANCE STATES, AS SHOWN FOR EXAMPLE IN FIG. 2, DUE TO A HIGH DENSITY OF MATERIAL IMPERFECTIONS, INCLUDING DEEP ENERGY &#34;TRAPS,&#34;BOTH AT THE HETEROJUNCTION INTERFACE AND IN THE HIGH RESISTIVITY GROWN REGION. THE DENSITY OF MATERIAL IMPERFECTIONS INCLUDING DOUBLE OR MORE ACCEPTORLIKE TRAPS MAY BE OF THE ORDER OF 10-18CM-3 OR GREATER.

DEFENSIVE PUBLICATION UNITED STATES PATENT AND TRADEMARK OFFICE Published at the request of the applicant or-owner in accordance with the Notice of Dec. 16, 1969, 869 O.G 687. The abstracts of Defensive Publication applications are identified by distinctly numbered series and are arranged chronologically. The heading of each abstract indicates the number of pages of specification, including claims and sheets of drawings contained in the application as originally filed. The files of these applications are available to the public for inspection and reproduction may be purchased for 30 cents a sheet.

Defensive Publication applications have not been examined as to the merits of alleged invention. The Patent and I Trademark Oflice makes no assertion as to the novelty of the disclosed subject matter.

PUBLISHED MAY 6, 1975 "reasons HETEROIUNCTION SWITCHING AND MEMORY DEVICE Int. Cl. I-I03k 17/56, 17/70 US. Cl. 35716 2 Sheets Drawing. 38 Pages Specification 5' But i 2T j g a),

A bistable switching and non-volatile memory device which may be read either destructively or non-destruc tively is provided, as shown in FIG. 5, using a heterojunction consisting of a heavily doped, single crystal, semiconducting material in electrical and mechanical contact with a different, high resistivity, semiconducting material. The heterojunction exhibits stable high and low impedance states, as shown for example in FIG. 2, due to a high density of material imperfections, including deep energy traps, both at the heterojunction interface and in the high resistivity grown region. The density of material imperfections including double or more acceptorlike traps may be of the order of 10' cm or greater.

M 6, 1975 H- J. HOVEL T9343) HETEROJUNCTION SWITCHING AND MEMORY DEVICE Original Filed April 7, 1972 2 Sheets-Sheet l HG, 1 FIG. 2

CURRENT CURRENT 1 J IFS 5 {B YRB 5 y VOLTAGE VOLTAGE? CURRENT 9 E r 15 VRB E 15 g W VOLTAGE T T T ENERGY BAND DIAGRAM Fl G 5 3 5GP 27 p I! l 23 21 28 INVENTOR HAROLD J HOVEL 29 25 1 Q/K/Q AT ORNEY May 6, 1975 HVEL T934,008

HETEROJUNCTION SWITCHING AND MEMORY DEVICE Original Filed April 7, 1972 2 Sheets-Shut 2 FIG. 6

FIG. 7

f GASI 5 75 II n I: GGP l \f [H Ill 1'" 1 1n III M 1 85 IL I I I Flea H. 11.. 

